New method for harvesting moisture from the air with organic crystal

March 16 () –

A novel method of capturing water from natural sources such as fog and dew has been presented in the magazine Nature Chemistry by researchers at NYU Abu Dhabi.

In the study, researcher Patrick Commins and postdoctoral associate Marieh B. Al-Handawi first observed the process of spontaneous condensation of water from its vapor to liquid form and its movement across the surface of a slowly sublimating organic crystal. This was found to be due to changes in the width of small channels that appear on the crystal surface over time and guide condensed water across the crystal surface.

The researchers describe the process of condensation and movement of water carrying particles on the surface of crystals of hexachlorobenzene, a compound often used as a fungicide. Due to sublimation, the surface of this material presents a rigid topography with defined parallel channels.

Small solid particles, such as dust or even metal nanoparticles, were observed to move autonomously along the channels. And they found that the movement of these particles was caused by condensed airborne water, which migrates through the channels due to the change in cross section and width of the channels over time.

Autonomous flow of water has previously been achieved using chemical surface modifications or precision-manufactured microchannels, or on the surface of natural systems such as some plants or insects.

The results of this new study can guide the creation of new technologies that take advantage of natural sources of water, such as dew and fog, which are currently used only by some desert plants and animals to survive.

The new research is based on the knowledge of the water uptake mechanisms of such biological structures, while presenting a fundamentally different mechanism for water transport.

“The movement of water over solid surfaces is one of the most fundamental phenomena in nature,” says Pance Naumov, director of the Smart Materials Laboratory and Center for Smart Materials Engineering, and an author of the study.

“Through millennia of evolutionary processes, the surfaces of natural organisms have been optimized to efficiently transport water and perform various vital functions,” he continues. Plants have been shown to do this by moving water against gravity.”

Naumov explains that they have discovered a new way to move water across a dynamic solid surface, a fundamentally new underlying principle of water collection. “This can serve as inspiration for emerging technologies that potentially could maximize the efficiency of experimental systems used for aerial moisture collection“, he assures.